Product Overview: This professional-grade multifunctional refrigerator tester is designed to evaluate and troubleshoot various components in refrigeration systems, including inverter boards, compressors, and other electrical components. Key Features: Application: Suitable for testing single and dual signal inverter boards, inverter compressors, single and dual dampers, pulse solenoid valves, 12V electrical switching valves, and DC-fans. Output Voltage: Available in 220V or 110V options. Electrical Throttle Detection: Connection: Attach the damper detection line to the damper motor interface, following the red, yellow, blue, and white sequence as shown in the diagram. Operation: The default setting is for single damper detection. Press the damper button; the damper indicator light will illuminate, and the display will show "176". When the damper is fully open, the light will turn off. Press the button again to close the damper; the display will show "176", and the light will turn off when fully closed. If the damper opens and closes smoothly, it indicates normal operation. If there is no movement or smooth operation, it suggests a malfunction. Package Includes: 1x Detection Kit